Internal combustion engine



2, 1932- A. H. KING ET AL 1,869,432

INTERNAL COMBUSTION ENGINE I Original Filed June 5, 1928 MEN 0/? S" 4; EXA/VDER /7. /1 //\/6 Patented Aug. 2, 1932 UNITED STATES PATENT OFFICE ALEXANDER H. KING AND EARLE A. RYDER, OF WEST HARTFORD, CONNECTICUT, ASSIGNORS TO THE PRATT & WHITNEY AIRCRAFT COMPANY, OF HARTFORD,

CONNECTICUT INTERNAL COMBUSTION ENGINE Original application filed .Tune 5, 1928, Serial No. 283,081. Divided and this application filed August 31,

1929. Serial This invention relates in general to internal combustion engines and is more particu larly concerned with thermostatic controls governing the operation of the same between certain ranges of combustion cylinder temperatures. This invention is a division from our original application, Serial Number 283,081, filed June 5, 1928, and is especially directed to such thermostatic devices as applicable to engine throttle control.

Internal combustion engines have a tendency to overheat under conditions of excess load, incorrect carburation due to the use of low grade fuels or improper adjustment of fuel proportions, incorrect spark timing and other adverse conditions. Such conditions frequently cause detonation, which in turn causes further overheating, poor lubrication, loss in horsepower output and the final seizing of the pistons within their cylinders and the destruction of the engine.

It is well recognized that failure of an engine due to overheating is due to excessive temperature of the cylinder head or cylinder walls, and this excessive temperature may be caused either by high combustion temperature, deficiency of the cooling system, or a condition such as detonation, which causes a disproportionate part of the heat of combustion to be transferred to the cylinder walls.

The prior art contains efforts to regulate engine temperatures by control of the cooling means, as, for example, thermostatic control of the cooling water circulation. Such means are effective to maintain a certain minimum temperature which may be desirable for operation, but are powerless to limit the maximum temperature of the combustion chamber or cylinder whenever the conditions of operation cause the evolution and transfer to the cylinder walls of more heat than the cooling system is capable of absorbing.

In order to remove the danger which might otherwise arise from excess loads, poor fuel selection, improper spark timing, deficiency of the cooling system or other causes of overheating, it is the purpose of this invention to provide a means, governed by cylinder temperature, for controlling the amount of heat supplied to the cylinder walls. In general any control is effective which operates to reduce the pressure and/or temperature of combustion; or to prevent detonation if conditions likely to cause detonation are present.

Combustion temperature may be lowered, and detonation, if any, reduced by partially closing the throttle, retarding the spark, enriching the fuel mixture, or by various combinations of the three.

It is the prime object of this invention to provide a supplemental throttle control, positioned between the main engine throttle control and the combustion chambers of the engine, and actuated by a thermostat influenced by engine temperature, for throttling the supply of fuel to said engine.

It is a further object of this invention to provide such a supplemental throttle control as will be independent of the operation of the main, or hand operated control.

Other objects of this invention will be found in the accompanying specification and claims and will be disclosed in the accompanying drawing in which The figure is a side elevation, partly in section, of my device as applied to an internal combustion engine.

At 1 we have disclosed a thermostat preferably, though not necessarily comprised of two metals of unequal coeflicients of expansion. One end of this thermostat is secured to the engine at a point on or adjacent to one of the combustion heads and the other is free to move under the torsional eflect of the temperature of the engine thereon. The thermostat 1 is pivotally connected at -50 to a rod 51 which, in turn, is pivotally connected to a throttle arm 52 mounted on the intake manifold 54 and controlling the movement of the throttle valve 53 therein. The main or hand operated throttle valve 55 is operated through the means of throttle arm lever 56 and throttle control rod 57.

From the foregoing our device will be seen to operate as follows:

Under influence of temperature increases the thermostat 1 will move into the position shown in dotted lines, due to the unequal coefficients of expansion of its component metals. This movement will result in a depression of the arm 51 with a rotating movement of the supplemental throttle 53 to partially close the same. This action Will artially throttle the engine to the end of reducing engine temperature and combustion pressures Without any movement of the main engine throttle control.

Having thus described our invention what We claim is In combination with an internal comb-ustion engine, an engine operating throttle control, a conduit leading from said throttle control to said engine, a supplemental throttle control mounted in said conduit and adapted to govern the passage of gas therethrough, said throttle normally being in open posi tion, a thermostat in thermal communication with said engine, and means operatively connecting said thermostat and said supplemental throttle control to actuate the latter when the engine temperature reaches a predetermined temperature.

In testimony whereof we have aflixed our signatures.

EARLE A. RYDER. ALEXANDER H. KING. 

